Automatic selective speed transmission



Oct. 27, 1936.

C. F. STAUFFER El AL AUTOMATIC SELECTIVE SPEED TRANSMISSION Filed June 25, 1952 4 Sheets-Sheet 1 Oct. 27, 1936.

c. F. STAUFFER ET AL AUTOMATIC SELECTIVE SPEED TRANSMISSION Filed June 25, 1932- 4 Sheets-Sheet 2 1935- c. F. STAUFFER ET AL 8,

AUTOMATIC SELECTIVE SPEED TRANSMISSION Filed June 25, 1952 4 Sheets-$heet 3 Oct; 27, 1936. c:..F.- STAUFFER ET AL. 2,053,736

AUTOMATIC SELECTIVE SPEED TRANSMISSION 4 Sheets-Shet 4 Filed June 25, 1932 Patented Oct. 27, 1936 AUTOMATIC sELEo'rIvE SPEED 'rnsnsmssion Charles F. Staulier, River Forest, and Simeon Budlong, Chicago, 111.; said Staufier assignor of twenty two-hundredths to Emil Barre, and

ten two-hundredths to James N. Budlong, both of Chicago, llll.

Application June 25, 1932, Serial No. 619,236

3 Claims. (Cl. ii-336) This invention relates to a means for transmitting power from an engine to a shaft driven thereby at speed ratios varying appropriately to the resistance encountered by the shaft.

One object of the invention is to providean improved means for automatically determining the ratio of movement in the driving and driven parts, to which end, the invention proceeds upon the principle of having a plurality of automati-a cally controlled clutches through which, respectively, a flywheel or other engine-actuated member may drive a plurality of transmitting members that determine the speed ratios; these automatically controlled clutches being so designed that they will establish drive at different speeds of the fly-wheel; but instead of having these clutches arranged in series in the sense that one drives through the other, the present invention introduces the important feature of combining, in anovel manner, independent transmitting members with two clutches arranged in parallel, so that each clutch may impart motion to the ultimate driven shaft independently of the other; and the further novelty, incidental thereto, of having 'the centrifugal actuating elements of the respective clutches both driven by and with a fly-wheel as an incident to the said parallel arrangement, but in such manner that when the engine is running at a relatively low speed, the low speed drive clutch will act to establish its drive, which is transmitted through suitable reduction gear to the driven shaft, and the high speed or one-to-one clutch will establish its drive only after the engine has picked up speed to a predetermined degree; the said one-to-onedrive being transmitted directly to the same driven member or shaft which the low speed drive clutch reaches only through reduction gearing; an overrunning clutch being introduced in the low speed} transmission to compensate for simultaneous parallel drive by the two transmissions of different ratio and permit the direct or one-to-one drive to run ahead of the reducing drive.

Another object of the invention is to provide what we call a compromise automatic speed like of another low ratio drive not involving the overrunning clutch'for use in holding back the vehicle by the engine in descendingsteep grades and, preferably, so designed that it will provide for a materially lower ratio of drive than the automatically selected low ratio drive; a collateral feature ofthe preferred embodiment of this part of the invention residing in the combinatiom of a-portion of the automatically selected low speed drive (not including the overrunning clutch) with reduction gears of p the manually selected low speed drive in order to get a doublereduction when conditions require. Still another novel feature of this part of the invention resides in the use of a speed reducing portion of the automatically selected low speed drive in series with the reverse drive which is, of course, voluntarily selected; and another novelty incident to this part of the invention consisting in utilizing the voluntary shifted dog clutch or its equivalent to establish the low speed series voluntarily selected drive, as well as low speed series, voluntarily selected reverse drive. Still another novel feature incident to thispart of the invention consists in utilizing an intermediate reduction member of the low ratio, automatically selected drive as a part or the train of connections to the low speed, volumtarily selected drive clutch as well as to the reverse clutch.

For purposes of illustration, this specification discloses a novel construction of clutch which functions with special advantage in coordination with several of the functions identifying the mechanism claimed herein: and this clutch, as one such instrumentality suitable for such claimed mechanism, will be briefly described indetail hereinafter.

In order that the invention may be more fully understood, an illustrative embodiment thereof will now be described indetail in connection with the accompanying drawings, in which- Figure 1 is a vertical axial section showing the application to a standard variable speed driving mechanism of parts which convert it into a transmission embodying the principles of the present invention.

Figure 2 is an elevational view, partly in secthrough means of which high ratio drive will be continued so long as load resistance renders it appropriate, and notwithstanding a reduction in speed suflicient to release the high speed centriiugal. clutch.

tion, of the transmission shown in Figure 1, mod-. 4

'ified to include a torque resistance clutch Figure 3 is an axial sectional view showing a detail of the torque resistance clutch.

Figure 4 is a transverse section on the line ke-4m of Figures 1 and 2, and showing by the upper half of the section the high speed centrifugal clutch, and by the lower half of the section the low speed centrifugal clutch.

Figure 5 is a transverse section on the line 5a:50: of Figure 1, showing in detail the overrunning clutch which permits the low speed centrifugal clutch and reduction drive to continue in engagement and mesh after the high speed centrifugal clutch is thrown in and while the drive is being transmitted at one-to-one ratio at such other high speed as may be provided for.

Figure 6 is a view similar to Figure 4, showing modified details inthe construction of the two clutches, and particularly those portions thereof which enforce simultaneous engaging and disengaging movements of the clutching units, and'developed from such movements limited circum- 'frential movements that insure gripping of the clutch elements during acceleration of the engine relatively to the vehicle or other power consuming unit and cause temporary disengagement during synchronization incident to. deceleration of the engine relatively to the power consuming unit.

Figure 7 is a segregated detail view of portions of the gripped or driven member of the clutch, including resilient means rendering it expansible and shock absorbing; and

Figure 8 is a partial axial section of parts shown in Figure 7 assembled as in use. In the'embodiment here selected for illustration, A represents a portion of an engine driven shaft; B a conventional fly-wheel mounted thereon and provided with teeth I) for receiving the pinion of a starting motor; 0 the driven shaft which, in an automobile, will be connected in conventional manner withthe driving axle or axles and here typifies a power consuming unit; D represents a shiftable dog-clutch member keyed to but axially slidable upon shaft C in response to the slide shaft E and gear shift lever F; G represents the high speed transmitting member with which.the clutch member D may be thrown into mesh to establish a one-to-one or other high ratio drive; H represents an idler pinion statidnarily located upon but rotatable relatively to shaft C with which the clutch member D may be thrown into mesh by rearward movement and which stands in driven relation to a conventional reduction gear countershaft I; and K represents a reversegear slidably keyed upon shaft C and adapted to be thrown into and out of mesh with a reversing idler L that stands in mesh with the countershaft I. The parts as thus far described may be of conventional form and, therefore, have been shown generally rather than in specific detail. They may be taken as representing one form of transmission mechanism in which the subject-matter of the present invention may be embodied and which, when combined with the sistance, to the high and low speed transmission members, respectively. The clutch herein shown in use for that purpose will now be described. I represents a low speed transmission member and 2 a high speed transmission member arranged concentrically with but rotatable relatively to the engine shaft A and the power consuming member C. 3 and 4 represent stationary jaws, respectively of the low speed and high speed clutches; and 5 represents a spider common to both these clutches, which carries concentrically responsive movable jaws 6 and I of said clutches. Bolts 8 secure the stationary jaws 3 and 4 and spider 5 to the fiy-wheel B, so that all of said parts are compelled to revolve at fly-wheel speed. 9 represents a driven member of the low speed clutch which is keyed at III to the low speed transmission member I; and II represents the driven member of the high speed clutch which is keyed at 12 to transmission member 2. The driven clutch members 9 and I I are provided with circumferential flanges 9a and Ila, respectively,

and I, cause the pairs of jaws to close into gripping relation to the said flanges. Each of the movable jaws 6 and 1, as will hereinafter appear, comprises an annular structure subdivided into segments in order to permit the member to expand under centrifugal movement and grip the driven member flanges, as referred to.

When under relatively low fly-wheel speed the low speed clutch 3, Ii, 9 imparts rotation to low speed transmitting member I, a pinion I3 carried by the latter drives the relatively larger and therefore speed reduction gear wheel I4 which, in turn, drives ,the concentric smaller pinion II that meshes at I6 with-the relatively larger drive gear G already referred to, so that if the shifting member D be thrown into mesh with gear G, automatically selected low speed forward drive will now be imparted to the power consuming member C orto the drive wheels of a vehicle with which it may be connected.

After the speed of the fly-wheel B increases to an appropriate R. P. M., the movable law I of the high speed clutch will respond to centrifugal force to grip the high speed driven member I I and thereby drive high speed transmitting member 2 which carries the gear wheel G, and the latter will then determine the speed of drive transmitted to member C. This high speed drive follows notwithstandingthe continued functioning of the low speed clutch 3, 6, 9, since at a suitable point between the low speed clutch and the driving gear G, for instance, between the gear wheel I4 and the pinion ii, there is located an overrunning clutch I I (see Figure 5) which permits pinion I! to be driven ahead of gear wheel I4. Hence, the present invention contemplates a plurality of automatically selective clutches interposed between the power producing and power consuming elements of the transmission, arranged in parallel in the sense that each is adapted to drive independently of the other, and both may perform their clutching functions at the same time without the low speed drive holding back the high speed drive, but with the low speed drive remaining in position to assume the drive whenever the high speed clutch relinquishes control.

For so much of the operation, gear wheel I4 75 and pinion I need only be mounted with freedom of rotation; but for additional functions performed in accordance with collateral features of the present invention, gear wheel It is keyed at Y Ma to the countershaft I so that the reducing portion I3, 14 of the automatically selected low speed drive (excluding the overrunning clutch ll) will also serve to impart rotation through gear It to the gear wheel H, which said gear wheel H, while idling about the power consuming element C whenever the drive is through gear wheel G, will become a part of the forward driving connection when shift member D is thrown into mesh with the clutch of gear wheel H, and thereby complete a manually selected positive low (conventionally termed intermediate) speed driving connection between the fly-wheel and the power consuming member which includes a portion of the automatically selectedlow speed drive and may be used .to check'th momentum of an automobile from the engine in descending steep grades or, with proper design of gear ratios, may constitute a higher power forward drive than that which is'secured by the automatically selected low speed drive alone. In a similar manner, countershaft I, driven by automatically selected low speed drive, may be used to operate still another forward drive similar to the first speed of the normal automobile transmission; towhich end, countershaft I is provided with another pinion it adapted to receive the pinion K when the latter is moved forward by the combined left-hand rocking movement and forward sliding movement of slide shaft E; and this low or first speed drive I, it, being in series with the automatically selected speed reduction it, it, constitutes the extreme high power forward drive of the system, according to the design selected for illustration.

Reverse drive, as already stated, is attained by throwing the slide gear K rearward with the gear shift lever F rocked to the left,,and this, too, is in series with the automatic low speed drive it, it and therefore involves ample power for all reverse purposes. a

From the foregoing, it will be seen that an important condition contemplated by the present invention is utilization of the automatically selected low and high speed drives to the exclusion of the both transmissions.

positive, manually selected, low speed hold-back drive; manually selected, positive first speed drive; and manually selected reverse drive. It will also be seen that these three additional drives, corresponding to drive normally provided in automobile transmission, are, respectively, in series with speed reducing gears of the automatically selected, low speed drive. Thus the apparatus described constitutes a combination of an automatic'variable speed transmission and a conventional H-shift type of manually selective trans mission, wherein the manual shifting lever of the manual transmission, in addition to its usual function, serves as a governing or conditioning means for the automatic transmission. Due to the close relationship of the automatic and manually selective transmissions, both structurally and in matters of function and control, certain of the elements described function as a part of For example, the clutch 3 and its associated gearing l3, l4 function in the low speed of the automatic operation as well as in the low, intermediate and reverse drives of the manually selective transmission. Similarly, the element D, when in its forward position, acts as a part of the automatic transmission, and forms the high speed drive of the manually selective transmission, while in its rear position it acts as a part of the positive or non-over-running intermediate drive.

As shown in Figures 2 and 3, the automatically selected low and high speed'drives herein described lend themselves with special advantage to use in combination with an automatically disengagedtorque resistance clutch, whereby the low speed transmission member i may enter into direct driving relation to the high speed transmission member 2, namely, through means of a friction clutch 2% introduced at some suitable point, such, for instance, as between the rear end of transmission member I and the gear wheel G; which clutch will cause low speed transmitting member i and high speed transmitting member 2 to revolve in unison under the drive of low speed clutch t, t, 9, accompanied by overrunning movement at clutch li, until such time as torque resistance shall be suihcient to cause slipping of the clutch 2d and pick-up of drive through overrunning clutch ll, which results in the transmission of torque resistance back through gears G, it, it, and id so as immediately to cause an axially forward displacement of pinion it by reason of the angularity of. its teeth through which it engages with a gear wheel i l, and torque resistance clutch it is thereby thrown out and leaves the automatically selected low speed drive to continue through the speed reduction gears it, id, id and G. The clutch 2t is urged toward closed position by a spiral spring it which surrounds the high speed transmission member 2 and acts between an adjustable nut it on the member 2 and an internal shoulder on the member 6 The driving function of the torque resistance clutch it will ordinarily occur only on deceleration following a drive through the high speed clutch, when the vehicle has momentum and road conditions are such as to impose low torque re-' sistance. It is desirable at such times, for the reason that it continues a one-to-one drive after the high speed clutch d, .l, i I! has, by fall in centrifugal force, been released from its gripping function.

As shown in Figure 4, which is an irregular section taken one-half through the high speed clutch and the otherhalf through the low speed clutch, the stationary clutch members 3 and t will be in the form of rigid rings, secured by bolts 8 to the fly-wheel B and having inwardly presented faces that receive linings of frictional material 3a, ta on the outer faces of the flanges 9a, lid of the driven members. 9 and M; also the movable jaws t and l of these clutches constitute in each instance an annular series of segments having sufficient mass to cause them to move by centrifugal force in opposition to retracting springs 2 l, 22 and thereby press their outer faces against the friction linings ta, lid on the inner faces of the flanges ta, lid to complete the clutching operabut by a floating member 25, 26 in the form of a continuous ring, in such manner that spring pressure on one side is transmitted to the opposite side of the spring and resistance, which must be overcome by centrifugal force in applying the movable jaw, is uniform throughout the annulus.

A further important feature of the matter of disposing of the centrifugal segments which make up' the movable jaw of a clutch, resides in the provision of the support between one end of each segment and the spider 5, whereby outward movement of a segment is caused to be accompanied by a limited circumferential movement of the jaw relatively to the flange (9a or Ila) of the driven member (9 or H) of the clutch in the direction opposite to rotation of the fly-wheel, so that on establishing contact between the movable jaw and the driven member, the grip of the jaw is automatically tightened by a toggle action; and, conversely, when decleration of the engine takes place relatively to the momentum of the car and the drag upon the clutch is in the opposite direction, there will be a series of momentary releases of the clutch until synchronizing is attained between the speed of the driving and driven parts of the clutch. According to Figure 4, the means for developing this toggle action consists of a series of links 21, 28, pivoted, respectively, at 21a,

28a to the spider 5, and at 21b, 28b to the segments 6 and 1. Only one toggle link 21, 28 is used for each segment, since the opposite end of the segment rests upon the shoulder 23 or 24 of the next adjacent segment and causes the segments to move bodily and uniformly throughout their arcuate dimensions.

According to Figure 6, the toggle effect upon the segments of the movable jaws and the clutches is developed by means of camming blocks 29, secured by pins 29a, 30a to the spider 5 and having faces at such angles to the radii passing through members are identical in construction, a description of one will suflice for both. As shown in Figure 7, these segments may consist of quadrants 9a: with a rim portion 9a.: that carries the flange 8a mounted upon said segment through means of resilient bushings 3| entering enlarged openings 32 in the rim segment and secured by rivets 33. The resiliency of the bushings M is sufficient to permit the rim members 9m: to be forced outwardly to bring their friction facings' against the stationary member of the clutch, as well as to return the rim portion out of frictional engagement when the clutch is released; also to absorb shocks in transmission.

What is claimed is:

1. A transmission of the class described combining rotary driving and driven members, a direct drive between said members including a friction clutch having disengageable rotary elements, a low speed drive for establishing driving C011? nection between said members and including a torque responsive thrust means connected to said friction clutch and operable by predetermined torque resistance in said low speed drive to hold said friction clutch open, and ineffective as a clutch-opening means while said elements of the clutch remain engaged and in the same rotative relationship to each other.

2. A transmission comprising a driving member and a driven member, high and low speed drives each including a centrifugally controlled clutch for automatically establishing driving connection between said members, said high speed drive in the acceleration of the driving member being adapted to take precedence over the low speed drive at a predetermined critical speed of the driving member. a frictional driving connection located between the low and high speed drives and operable to maintain a high speed driving action from the low speed clutch to the driven member when said driving member falls below the critical speed of said high speed clutch, said low speed connection embodying inter-acting torque responsive elements operable to control the opening and closing of said frictional driving connection.

3. An automatic transmission for automobiles and the like comprising, in combination; a rotatable power supply shaft, a driven power output shaft, a high speed friction clutch having driving and driven elements adapted to be engaged to "establish a power-transmitting relationship therebetween, the driving element of said clutch being connected for rotation .by said power supply shaft, a low speed friction .clutch having driving and driven elements adapted' to be engaged to establish a power transmitting relationship therebetween, the driving element of said low speed clutch being connected for rotation by said power supply shaft, an H-shift-type manually selective change gear transmission having a manually engageable shifting device, said man'- ually selective transmission including a counter-shaft having a non-over-running reduction gear connection with the driven element of said low speed clutch so as to be rotated thereby, a

ble member engageable by said shifting device for movement thereby to establish a low speed forward driving connection between said counter shaft and said driven shaft, to disconnect said counter shaft from said driven'shaft, or to establish a reverse driving connection between said counter shaft and said driven shaft, a second shiftable member forming a part of said manually selective transmission and engageable by said shifting device to move said second member from a neutral position to a second position to establish a direct forward driving'relationship between the transmission shaft of said high speed clutch and said driven shaft, or to a third position, gearing means cooperating with said second member while in said third position to establish an intermediate non-overunning forward driving connection between driven shaft, and means connected) to said clutches and operable inresponse to a running function of an engine to engage said low and high speed clutches in succession.

id counter shaft and said 

